Machine for the tooling of metallic screw propeller blades



Dec. 14, 1937. 2,102,505

MACHINE FOR THE TOOLING OF METALLIC scmaw PROPELLER BLADES C, W. BERTHIEZ Filed March 26, 195'! 2 Sheets-Sheet 1 INVENTOR CHARLES W. BERTHIEZ by his qfrarnvgs Dec. 14,1937. 7 c w BERTH|EZ 2,l@2,505

MACHINE FORJIAHE TOOIJING 0F METALLIC SCREW PROPELLER BLADES Filed March 26, 193'? '2 Sheets-Sheet 2' Fig. 4'.

INVENTOR kg iris dfibrneys CHARLES w. BERTHlE Z Patented Dec. 14, 11937 UNITED sTATE s PATENT OFFICE aroasos MACHINE FOR THE TOOLING OF ME'IALHC SOREW PBOPELLEB BLADES Applicationllltiiarch 28, 1937, Serial No. 133,257

France April 2, 1936 2 claims. (Cl. 90-136) I The present invention relates to machines employed forthe tooling or machining of metallic screw propeller blades, by means of milling cutters or like tools, according to a blade serving as pattern, in which machines the pattern to be reproduced and the parts to be machined receive synchronized movements of rotation around parallel axes and the tools receive displacements, corresponding to those of the feelcr in contact with the pattern to be reproduced, perpendicular to those axes of rotation of the blades and patern.

their movement of rotation at both their extremities.

' By placing the blades under, an axial tension, that is to say in the vertical direction, an abnormal tensional force during machining is suppressed and all bending is eliminated; on the other hand, the simultaneous rotary driving at the two extremities obviates the torsion of the blades and allows a rational machining of them.

There can moreover be provided, at an intermediate point in the length of each of the blades, a guiding ring of which the movement is likewise driven; which allows the centering and the driving of this-blade at that point, in addition to the driving at the two extremities, in synchronism' with the latter; in this way the forces of flexion and torsion are still further reduced.

Theinvention is described hereafter in-a detailed manner with'reference to the accompanying drawings, which represent one example of 5 carrying it into operation:

Fig. 1 is a view more or less diagrammatic in front elevation ofthe machine, parts in vertical e In machines of this kind employed hitherto,

the blades to be tooled are placed in a horizontal 15 position; this gives rise to deformations of the intermediate driving and centering rings, respectively; and t Fig. 'l is a view in horizontal section on a larger scale through the guiding ring, along the line 1-1 of Fig. 6. 5 Upon the base a of the machine are fixed two enduprlghts I) connected together by horizontal cross members c, upon which are fitted intermediate uprights b the uprights b and b comprise on their front vertical face, vertical slides 10 balong which can travel carriages d, support- 'lng a horizontal cross member e; the latter is mounted upon the carriages d by means of a series of rollers having horizontal and vertical axes respectively d d (Figs. 1 and 2). 15 The carriages d and the cross member 0 can receive a vertical feed movement by the intermediary of screws d journaled vertically in the end uprights b and in the central intermediate upright b, which engage with a part d forming 20 a nut upon the rear face of the corresponding .carriage d (Fig. 2); the screws d are actuated by bevel pinions at d driven from the change speed box (not represented), located in the base of the machine. I 26 Upon the vertical slideways of the uprights b b there can likewise slide another horizontal cross member f; the latter can be raised or lowered by means of screws f journaled vertically in the end uprights b and engaged with 30 parts I forming nuts upon the rear face of the cross member I; these screws 1' are likewise actuated by bevel pinions f meshing with bevel pinions f4, secured to a cross shaft I; this shaft 1 may be rotated through a chain (not shown) engaging a sprocket wheel I, secured to said shaft f, or in any'other suitable manner. The upper cross member carries movable head stocks a, serving for the driving of the screw propeller 4o blades h at their upper extremity as will be described hereafter.

Upon the cross member e are mounted the head stocks i carrying the milling cutters 1 having vertical axes, serving for the machining of the blades h, as well as the head stock i likewise having a vertical axis, carrying the copying roller d which comes in contact with the screw propeller blade 72. serving as the pattern tobe reproduced by machining of the other blades h.

The milling'cutters 7 and the copy g roller 7' are constantly maintained in contact with corresponding screw propeller. blades h n by the action of a counterweightch suspended from a cable attached to the cross member e having a horizontal sliding movement in the carriages :1.

Each of the propeller blades h. h. is driven at its lower extremity from the following device (Fig. 5); the lower trunnion h of each blade isclamped by locking dogs k to a plate is (these dogs being fixed in the customary manner by bolts It to grooves 10 of inverted T-shape starting from the upper face and from the periphery.

of the plate It) this plate It is in its turn fastened by dowels to a gear meshing with a spur toothed pinion k keyed upon a vertical driving shaft Z, which extends over the whole height of each blade, as far as the movable head stock .at the upper extremity of the latter.

Each propeller blade is likewise centred and driven at an intermediate point of its length by the following device (Figs. 6 and 7): the blade h is surrounded by a. ring m formed in two halves connected together and leaving between them a gap m into which the blade passes; on the two sides of the blade there act plungers n opposed in pairs; each plunger it is subject to the action of a spring n bearing upon a screw 11., adjustable in position in a recess m in one of the halves of the ring m (Fig. 7); ashoulder m limits the stroke of the plungers n towards'the blade.

Around the ring m is keyed a spur toothed crown m meshing with a pinion o, keyed upon the vertical shaft 1 and fast with a helicoidal wheel 0 the latter is in mesh with a helicoidal wheel 0 fixed upon a horizontal shaft 0 extend- Each propeller blade h h is driven at its upper extremity by the following device (see in particular Fig. 4) the upper trunnion h of the blade is clamped in a split conical mandril p by a screw threaded ring p forming a nut; the trunnion is centred by a point p in the driving plate 11 comprising on its lower face a socket p, in which the mandril p is clamped by the ring p this plate p meshes with a toothed pinion q keyed upon the vertical shaft 2, (of which the movement of rotation is driven, as described abovefby the transmission 0 o 0 o 0 0 The plate p is iournaled as also is the pinion q, in the head stock 17. which is mounted upon a slide 1', upon which it can receive a slight vertical displacement; this is produced by a worm r adapted to be actuated by hand and meshing with a helicoidal wheel 1', fast with a vertical screw r joumaled in the slide and engaging with a nut 1 fast with the head stock a. This mechanism allows a precise adjustment of the vertical position of each of the headstocks 0, according to the length of each blade h, after the upper cross member j,'supporting the different head stocks 0, has been brought in the manner previously described to the level corresponding approximately to the length of all the blades h h In this way each of the blades can be put under a suitable axial tension, in such a way as to suppress the forces of flexion during machining.

The upper driving plate p, as well as the pinion q are iournaled in the head stock a by the intermediary of ball thrusts and'bearings, in order to absorb the tension exerted What I claim is: 1. A machine for the tooling of metallic screw propeller blades according to a blade serving as a pattern, comprising a blade pattern. and a set of blade blanks to be tooled arranged with their upon the blade.

axis in a vertical position, means for giving to the blade pattern and to the blade blanks syn- ,chronous movements of rotation around their parallel vertical axes, a feeler adapted to engage with the blade pattern to be reproduced, a set of cutting tools adapted to engage with the blade blanks to be tooled, means for displacing the feeler along the blade pattern and means for giving to the tools displacements corresponding to those of the feeler, perpendicular to the axes of rotation of the blade blanks and of the blade pattern, means for maintaining said feeler and said tools in engagement with the blade pattern and blade blanks respectively, during said displacements, in combination with means for maintaining each of the blade blanks and the blade pattern under axial tension during tooling, and with means for driving each of the blade blanks and the blade pattern at both ends during its movement of rotation.

2. In a machine as'claimed in claim 1, the provision of means for centering and driving each of the blade blanks and the blade pattern at a point intermediate of-its length, in synchronism with the means driving each of them at its both ends. 7

cnaams WILLIAM nna'rnmz- 

